We have prospectively evaluated a cohort of 380 diabetics from Rochester, MN and have found:1) the cohort is representative of diabetics in Rochester, MN; 2) approximately one-half do not have neuropathy; one-third have asymptomatic neuropathy without weakness of foot dorsiflexion; and 15% of ID and 12% of NID diabetics had symptomatic neuropathy but only 6% and 1% of these, respectively, had weakness of foot dorsiflexion; 3) neuropathy test results were sufficiently, had weakness of foot dorsiflexion; 3) neuropathy test results were sufficiently sensitive to detect statistically significant worsening in 24 mo; and 4) various risk factors were found to be correlated with staged severity of neuropathy and also with change in neuropathy test results. Because we have recruited a unique diabetic cohort, representative of Rochester diabetics, have demonstrated that they can be maintained in study over long times, shown that the battery of nerve evaluations obtained at periodic intervals are sensitive, reproducible, and meaningful of neuropathic change, and that the cost is modest by comparison to other studies of this type, this study is now to be extended for a further 5 years with the following objectives in mind: 1) extending the prevalence estimates to carpal tunnel syndrome (CTS), cranial neuropathy (CN), proximal asymmetric neuropathy (PAN), truncal radiculopathy (TR), and autonomic neuropathy (AN) and assessing for the prevalence of these neuropathies in a control population; 2) determining the course of neuropathy (and of test results) over a period of 8 years to refine rates of progression and outcome; 3) validate which minimal criteria for polyneuropathy (and also of CTS, CN, PAN, TR, and AN) and criteria for staged severity are best; and especially 4) critically evaluate the influence of a variety of risk factors (serially evaluated oer many years to ensure that they are representative and valid measures) for alterations in staged severity of neuropathy and also for neuropathy test results (evaluated over at least 8 years to ensure that a measurable change has occurred in sufficient patients to allow a robust assessment of such risk factors as glycemic control, nephropathy (creatinine and microalbuminuria), hypertension and hyperlipidemia (cholesterol, triglycerides, lipoproteins, and apolipoproteins). Also to be assessed are whether certain risk factor alterations might predict cardiac death (through arhythmia or heart attack), stroke, CTS, AN, PAN, TR, sexual impotence in the male, Charcot joints, plantar ulcers, or related phenomena.